Grinding apparatus



Dec. 24, 1968 L. M. TIPTON 3,417,800

GRINDING APPARATUS Filed July 21, 1966 5 Sheets-Sheet l Fig L INVZ'NTGRLarry M Eaton 2/617 414; 21M aw; i/m mo Af/omeqs Dec. 24, 1968 L. M.TIPTON 3,417,300

GRINDING APPARATUS Filed July 21, 1966 I5 Sheets-Shet 2 82 I I"INVENTOR.

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Dec. 24, 1968 M, TIPTON GRINDING APPARATUS 5 Sheets-Sheet Filed July 21,1966 IIZ United States Patent Office 3 Claims. or. 146-186) ABSTRACT OFTHE DISCLOSURE Apparatus for grinding and chopping meat including acutter plate assembly made up of a plastic backing plate and a metalface plate. Another embodiment of the cutter plate assembly includes aplurality of stacked metal cutter plates.

The present invention relates to meat grinding and food chopping and isa continuation-in-part of my copending application Ser. No. 329,669, nowPatent No. 3,286,551.

Presently available meat grinding devices incorporate a cast cutterblade and a one-piece cast plate. It has been found that slightmisalignment of the plate and blade of such a device will result inuneven wear of the cutting surfaces. One object of the present inventionis to provide a grinder incorporating parts which are less expensive andmore flexible than previously used cast parts. Another object of theinvention is to provide a grinder incorporating automatic means forpreventing uneven wear of the cutting surfaces of the plate and blade ofthe grinder.

Still another object of the invention is to provide an improved devicefor grinding or chopping food and meat.

A further object of the present invention is to provide an improvedcutter plate assembly.

Related objects and advantages will become apparent as the descriptionproceeds.

One embodiment of the meat grinder of the present invention mightinclude a cylindrical housing, a plurality of parallel plates having aplurality of aligned openings therethrough, said plates being arrangedin stacked engagement with one another, an annular internally threadedcap threadedly received on the end of said housing, a worm coaxiallyreceived in said cylindrical housing and having a reduced square shapedportion on the end thereof and a further reduced cylindrical portion onthe end of said square shaped portion, an annular bearing mounted on oneof said plates, said cylindrical portion being received in said bearing,a cutter blade received on said square shaped portion in engagement withsaid stack of cutter plates and being shaped generally as a four pointedstar.

The full nature of the invention will be understood from theaccompanying drawings and the following description and claims:

FIG. 1 is a longitudinal section of a grinder embodying the presentinvention.

FIG. 2 is a plan view of a cutter plate making up a portion of thestructure of FIG. 1.

FIG. 3 is a plan view of a further cutter plate making up a furtherportion of the structure of FIG. 1.

FIG. 4 is a plan view of an annular retainer making up a further portionof the structure of FIG. 1.

FIG. 5 is a perspective view of a cutter blade making up a still furtherportion of the structure illustrated in FIG. 1.

FIG. 6 is a plan view of a cutter plate such as the one illustrated inFIG. 2 showing an intermediate step in the manufacture of the cutterplate.

FIG. 7 is a vertical section through a cutter plate and 3,417,800Patented Dec. 24, 1968 apparatus for operating on the cutter plate andshowing a preliminary step in the manufacture of a cutter plate.

FIG. 8 is a view similar to FIG. 7 showing a further step in the processof manufacture of the cutter plate.

FIG. 9 is a view similar to FIGS. 7 and 8 and showing a still furtherstep in the manufacture of the cutter plate.

FIG. 10 is a view similar to FIGS. 79 showing the final cutter plateafter manufacture thereof is complete.

FIG. 11 is a view similar to FIG. 1 of an alternative embodiment of thepresent invention.

FIG. 12 is a plan view of a cutter plate assembly forming a part of thestructure of FIG. 11.

FIG. 13 is an exploded perspective view of a cutter blade or cutterblade assembly forming a part of the structure of FIG. 11.

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to the embodiment ilustrated inthe drawing and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of theinvention is thereby intended, such alterations and furthermodifications in the illustrated device, and such further applicationsof the principles of the invention as illustrated therein beingcontemplated as would normally occur to one skilled in the art to whichthe invention relates.

Referring more particularly to FIG. 1, there is illustrated a grinderincluding a housing 10. The housing 10 has a cylindrical chamber 11which is fed by a vertical passage 12. Received within the housing 10and the cylindrical chamber 11 is a Worm 15 which can be driven by anarm 16 received upon a square shaped end portion 17 on the worm. Theworm 15 is journalled within a cylindrical opening 20 at one end of thehousing 10 and has a reduced diameter portion 21 which is joumalledwithin a bearing 22 at the opposite end of the housing 10. The arm 16 issecured to the worm 15 by a screw 18 having a flange 19 retaining washer23 and the arm 16 on the portion 17.

The worm 15 is rotated in such a direction as to move meat and the likeleftwardly as viewed in FIG. 1 along the cylindrical chamber 11 from thepassage 12. Worm 15 has a square shaped portion 25 joining its reduceddiameter portion 21 and the cylindrical stem 24 of the worm. A pluralityof cutter plates 26 are held in position at the end of the chamber 11 bymeans of an annular retainer 27 and an annular internally threaded cap30 which is threadedly received on the end of the housing 10. A cutterblade 31 is received upon the square shaped portion 25 and rotates withthe worm 15 to cut and mash against material being pressed up againstthe stack of plates 26 whereby the worm can force the material throughthe aligned openings 32 in the plates 26.

It will 'be noted that all of the plates 26 are not identical in thatthe plates 26B do not include the central flange 35 of the plate 26C.The bearing 22 (also shown in FIG. 3) is fixedly mounted within thecentral flange 35. In other respects, however, the plate 26C isidentical to the plates 263. The various apertures 32 through the plates26B and 26C are maintained aligned by the retainer 27 which has threeinwardly projecting portions 36 extending into three recesses 37 in theouter peripheries of each of the plates 26B and 26C.

Referring to FIGS. 5 and 1, the cutter blade 31 is hollowed out at 40,said hollowed out portion 40 opening on the face of the blade whichengages the stack of cutter plates 26. The cutter blade 31, therefore,has a portion 41 which surrounds the hollowed out portion and whichengages the first of the two cutter plates 26B. It has been found thatthe construction illustrated in FIG. 5 is selfsharpening and because ofthe two contact portions 45 and 46 of each cutter blade arm 42, thefollowing portion 46 of the cutter blade arm scrapes clean the cuttingface of the cutter plate 26B. It has been further found that the twoportions and 46 of each contact arm 46 increase the stability of thecutter plates and blade assembly in the meat grinder. It will be notedthat the portion 45 of each cutter blade arm is flat while the portion46 of each cutter blade arm curves around and meets the portion 45. Thecutter blade arms are so designed because the cutter blade 31 rotates inthe direction of the arrow 47 and, therefore, the material being forcedthrough the openings 32 is pushed ahead of and upon the surface 45 ofeach arm.

Referring now to FIG. 6, the manner in which the cutter plate 26B or 26Cis manufactured is illustrated. A stamping device, shown schematicallyin FIGS. 7-9, is indexed through repeated ten degree angles to repeatthe stamping pattern shown at 50, thus the dotted lines at 51 show thelocation of the next set of apertures to be stamped. Since such indexingand stamping of sheet metal is conventional, the conventional apparatusused is not illustrated.

Applicants invention does include, however, novel stamping or punchingmeans for forming the apertures 32 in a cutter plate 26. Such stampingmeans might include the above mentioned indexing apparatus or might beindependent thereof. This novel apparatus includes a support 55 having acylindrical opening 56 therein, said cylindrical opening having its axisperpendicular to the surface 57 of the support and meeting the surface57 at a relatively sharp edge 60. A cutter plate 26 to be stamped isplaced upon the support 55 and is punched by the punch element 61. Thepunch element 61 includes a distal portion 62 which is cylindrical andwhich has a sharply squared off distal end 65. Adjoining the cylindricalportion 62, which is of the same diameter as the opening 56, is afrusto-conically shaped surface 66 which converges inwardly away fromthe distal portion 62 and is coaxial of the cylindrical portion 62.

A further frusto-conical portion 67 has a greater apex angle than thefrusto-conical portion 66 and flares outwardly generally toward thedistal end of the punching element 61. A cylindrical surface 70 islocated proximally of the cylindrical portion 62 and has a greaterdiameter than said portion 62. The cylindrical portion 70 adjoins andintersects the frusto-conical portion 67 to define a sharp edged punch71 spaced radially outwardly of the sharp edged punch surface 62 definedby the intersection of the distal end 65 and the cylindrical portion 62.

The steps of the process of the present invention are shown serially inFIGS. 79. It can be seen that the punch edge 72 first is used to punchthrough the plate 26 into the opening 56. This results in a deforming ofthe plate in such a manner that the surface 75 is rounded off. It isnecessary, however, in the final cutter plate 26 to have a sharp edge atthe juncture of the cutter plate aperture 32 and the surface of thecutter plate against which the blade 31 rotates. The annular punchportion 71 functions to punch out a recess 76 surrounding the opening32. The punching of the recess 76 causes the material 77 adjacent theopening to move upwardly and inwardly to the position shown in FIG. 8.The punch element 61 is then withdrawn from the support 55 and thecutter blade 26. The frusto-conical surface 66 of the punch elementcauses the material 77 to be pushed outwardly and still further upwardlyso that the opening 32 is cylindrical throughout its entire length. Itwill also be noted that the material 77 extends upwardly above thesurface 80 of the cutter plate 26.

The next step of the process is the grinding off of the surface 80 toremove the portion of the material 77 which projects above the surface80 and to align the remaining portion of the material 77 with thesurface 80 to achieve the result illustrated in FIG. 10. It will benoted in FIG. 10 that a sharp edge is provided at 81 where the surface80 intersects the surface of the aperture 32. The sharp edge 81 is veryuseful in the grinding operation since it cooperates with the cutterblade 31 to shear the food or meat.

It will be evident from the above description that the present inventionprovides a meat grinder including parts which are less expensive andmore flexible than previously used cast parts. This is true because ofthe fact that the two cutter plates 268 can be reversed and/orinterchanged to provide additional sharp cutting surfaces against whichthe blade 31 can operate when the cutting surfaces of a plate aredulled. It can be seen that the edge 82 (FIG. 10) of the cutter plate 26will be sharp because of the particular punching action by which it ismanufactured and that no formation of a recess such as 76 is necessaryto provide the proper sharp edge at surface 83.

Referring now more particularly to FIGS. 11, 12 and 13, there isillustrated an alternative embodiment of the grinder of FIGS. 15. Thegrinder of FIGS. l1, l2 and 13. is identical to the grinder of FIGS. l-Sexcept as described below. In other -words, the portion of the grindernot shown in fragmentary FIG. 11 is identical to the grinder of FIG. 1.

Referring to FIG. 11, the grinder includes a housing having acylindrical chamber 101 through which food or the like is driven ormoved by means of a worm 102. The worm 102 has a reduced diameterportion 105 which is journalled within a bearing 106 at the end of thehousing 100. The worm 102 is rotated in such a direction as to move meatand the like leftwardly as viewed in FIG. 11 along the cylindricalchamber 101. The worm 102 has a square shaped portion 107 joining itsreduced diameter portion 105 and the cylindrical stern 110 of the worm.

A pair of plates 111 and 112 are held in position at the end of thechamber 101 by means of an annular retainer 115 and an annularinternally threaded cap 116 which is threadedly received on the end ofthe housing 100. A cutter blade or cutter blade assembly 121 is receivedupon the square shaped portion 107 and rotates with the worm 102 to cutand mash against the material being pressed up against the stack ofplates 111 and 112, whereby the worm can force the material through thealigned openings 120 in the plates 111 and 112.

The plate 111 mounts or has formed integrally therewith the bearing 106.The plate 111 is formed of plastic such as, for example, nylon so as toprovide a relatively soft or resiliently deformable material formounting of the plate 112 which cooperates with the cutter blade 121 tocut and extrude the material being operated upon in the chamber 101.Because of the fact that the cutter plate 112 is easily removed andreplaced, maintenance of the grinder is made relatively easy.

Referring to FIG. 12, the manner of mounting of the cutter plate 112 onthe backup plate 111 is illustrated. The plate 112 has three radiallyoutwardly extending fingers 122 which are received within slots 123 inthe backup plate 111. The slots 123 extend first axially of the backupplate 111 from the rightward face thereof as illustrated in FIG. 11 andthen extend rotationally in a clockwise direction as the plate is viewedin FIG. 12. At the base or deepest portion 117 of each of the slots 123there is imbedded a pin 118 which acts as a limit for movement of thefingers 122. It can be appreciated that the pins 118 act to limit therotation of the cutter plate 112 when the openings 120 of the cutterplate 112 are aligned with the openings 120 of the backup plate 111.

The backup plate 111 is held against rotation relative to the retainer115 in exactly the same manner that the plates 26A and 26B are heldagainst rotation relative to the retainer 27, that is, by means of threerecesses 125 in the outer periphery of the plate 111 and by the threeinwardly projecting portions 126 which extend into the three recesses125 and engage the plate 111 in a friction fit relationship.

Referring to FIG. 13, the cutter blade or cutter blade assembly 121includes a cutter blade insert 130 and a cutter blade mount 131. Thecutter blade mount 131 has a hub portion 132 and has four radiallyextending arms 135, said hub portion 132 being hollowed out to receivethe insert 130. The insert 130 is generally a flat piece of metal whichhas been punched at its center to form a rectangular flange 136 whichfits over and grips the similarly shaped but smaller flange 137 forminga part of the hub 132. The rectangular shapes of both of the flanges 136and 137, of course, operate to prevent rotation of the insert 130relative to the mount 131.

The cutter blade insert 130 has a leading portion 140 on each of itsarms 141, which leading portion is straight, while the following portion142 of each cutter blade arm 141 curves around and meets the portion140. The cutter blade arms 141 are designed in this manner because thecutter blade 121 rotates in the direction of the arrow '145 and,therefore, the material being forced through the openings 120 is pushedahead of and upon the surface 140 of each arm 141. The junction of eachportion 140 and the front face 146 of each arm 141 is sharpened toprovide a cutting surface to cooperate with the sharp openings 120 inthe cutter plate 12. Because of the relatively inexpensive constructionof the cutter blade insert 130, it is very easy and convenient andeconomical to remove the cutter blade insert 130 and to replace it witha new insert instead of attempting to sharpen the cutting edges of theinsert.

It should be mentioned that the backup plate 111 includes a cylindricalportion 150 which is located at the outer periphery of the backup plate111 and which extends or projects rightwardly as viewed in FIG. 11 so asto receive and cup therewithin the cutter plate 112. One of theadvantages of the use of the plastic backup plate 111 is the fact thatit is resiliently deformable and, consequently, provides an automaticmeans for preventing uneven wear of the cutting surfaces of the plate112 and the cutter blade 121. Also, the backup plate 111 automaticallyprovides the bushing 106 which can be cast integrally with the backupplate.

It can be seen that the cutter plate assembly of the present inventionprovides the advantage of a retainer ring in both of the illustratedembodiments, said retainer ring facilitating the handling of the cutterplate assembly outside of the grinder such as, for example, when thecutter plate assembly is being stored. Of course, the cutter plateassembly referred to in the preceding sentence is either the cutterplate assembly made up of the three stacked plates 26A and 26B and theretainer 27, as well as the bearing 22, and also the cutter plateassembly made up of the retainer 115, the backup plate 111 and thecutter plate 112. As mentioned above, one of the advantages of the firstdescribed embodiment of the grinder is the fact that the two plates 26Bcan be used interchangeably to provide a new or fresh cutting surfaceagainst which the blade 31 can operate. Also, the plates 26B can bereversed in their direction so that the backside thereof can be used.This is also true of the cutter plate 112 of the embodiment of FIGS. 11,12 and 13.

While the inVentiOn has been illustrated and described in detail in thedrawings and foregoing description, the same is to be considered asillustrative and not restrictive in character, it being understood thatonly the preferred embodiment has been shown and described and that allchanges and modifications that come within the spirit of the inventionand the scope of the claims are also desired to be protected.

The invention claimed is:

1. A grinder comprising a cylindrical housing; a plurality of parallelplates having a plurality of aligned openings therethrough, said platesbeing arranged in stacked engagement with one another, an annularretainer receiving said plates, means for maintaining the openings ofsaid plates in alignment, an annular internally threaded cap threadedlyreceived on the end of said housing and receiving said retainer andplates and holding them against said housing, a worm coaxially receivedin said cylindrical housing and having a reduced square shaped portionon the end thereof and a further reduced cylindrical portion on the endof said square shaped portion, an annular bearing mounted on one of saidplates, said cylindrical portion being received in said bearing, acutter blade received on said square shaped portion in engagement withsaid stack of cutter plates and being shaped generally as a four-pointedstar, said plurality of plates including a plastic plate and a metalplate, said plastic plate being resiliently deformable, said means formaintaining said openings of said plates in alignment comprising saidmetal plate having radially outwardly extending fingers, said plasticplate having radially outwardly extending slots adapted to receive saidfingers, said metal plate being rotatable relative to said plastic platewith said fingers in said slots to secure said metal plate to saidplastic plate, said plastic plate and said retainer having mutuallyengaging projections and recesses.

2. The invention of claim 1 additionally comprising metal pins eachembedded in said plastic plate at the base of a respective one of saidslots, said metal pins acting as limits for said fingers for positioningsaid openings in alignment.

3. A cutter plate assembly comprising a plurality of parallel plateshaving a plurality of aligned openings therethrough, said plates beingarranged in stacked engagement with one another, an annular retainerreceiving said plates, said plurality of plates including a plasticplate and a metal plate, said plastic plate and said retainer havingmutually engaging projections and recesses, said metal plate havingradially outwardly extending fingers, said plastic plate having radiallyoutwardly extending slots adapted to receive said fingers, said metalplate being rotatable relative to said plastic plate with said fingersin said slots to secure said metal plate to said plastic plate, and aplurality of metal pins each embedded in said plastic plate at the baseof a respective one of said slots, said metal pins acting as limits forsaid fingers for positioning said openings in alignment.

References Cited UNITED STATES PATENTS 431,230 7/1890 Leopold 146-1891,080,875 12/1913 Mayfield et a1. 146189 X 1,122,055 12/1914 Asbury146-189 1,514,271 11/1924 Tilden 146189 1,695,898 12/1928 Laemmel 1461892,916,069 12/1959 Williams 146189 FOREIGN PATENTS 875,566 6/1942 France.

Ad. 8,937 1904 Great Britain.

W. GRAYDON ABERCROMBIE, Primary Examiner.

